Sorry have no idea
We don't think so, American dollars are not very populair in Cuba. I don't think you can pay with them anywhere in Cuba
Not sure about Dona Eutimia specifically but many restaurants (and taxis and shops) do accept CUC or USD (or euros) since the conversion is 1 to 1. This is great because you avoid the 13% penalty on American dollars. We paid in the local tourist currency (CUC) at this restaurant (after converting euros picked up in a prior trip to Europe).
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